This study finds support for agenda melding and further validates the Network Agenda Setting (NAS) model through a series of computer science methods with large datasets on Twitter. The results demonstrate that during the 2012 U.S. presidential election, distinctive audiences “melded” agendas of various media differently. “Vertical” media best predicted Obama supporters’ agendas on Twitter whereas Romney supporters were best explained by Republican “horizontal” media. Moreover, Obama and Romney supporters relied on their politically affiliated horizontal media more than their opposing party’s media. Evidence for findings are provided through the NAS model, which measures the agenda-setting effect not in terms of issue frequency alone, but also in terms of the interconnections and relationships issues inside of an agenda.